Smoky Bracelets: The Transformative Stone If you're looking for a stunning and powerful crystal, smoky quartz is the gemstone for you! Its ominous appearance is due to the radiation within the Earth's crust and the high temperatures it is exposed to during formation. This gemstone is unique, with shades ranging from light to dark brown and black. But that's not all - it can also have a yellow or orange tint! Smoky quartz exists worldwide, including in Colorado, Brazil, India, Russia, Scotland, and Africa. Astrologically speaking, it is related to the signs of Sagittarius, Scorpio, and Capricorn.